refactor: remaining game messages as structs, switch removed

Every game message still written or read by hand is now a NetGameMsg with
Serialize and Deserialize, in per-domain files:
- MovementMessages: teleport, platforms (resync and its request), orient to
  angle, node rotation lock, gravity scale, jetpack mode, control scheme,
  respawn checkpoint, rails (set/start, ready, cancel, arrived), mount
  inventory ID, dismount complete, possession ack, ghost reference override
  and position, camera cycling (eCameraTargetCyclingMode moves here).
- ZoneMessages: player loaded (the old PLAYER_LOADED case), ready for
  updates, player ready, restore to post load stats, server done loading,
  invalid zone transfer list, zone summary display/dismissed, level
  processing complete, object world state, and the localized announcement
  WorldMigration wrote by hand.
- PlayerMessages: chat mode, GM level, LEGO score, currency, reputation,
  GM invis, pickup currency, zone and player statistics, chat commands, bug
  reports, verify ack.
- ObjectMessages: fire event client/server side, notify client
  (zone) object, notify object, script network vars, failed preconditions,
  terminate interaction, set name, request use, request server object info.
- QuickBuildMessages: notify state, enable, cancel.
- ActivityMessages gains match response/update/request, leaderboard request
  and data, shooting gallery score/rotation/fire, activity state change.
- MissionMessages gains MissionDialogueCancelled (a no-op, as before).
The wire structs left in GameMessages.h move to their domains (tooltip and
emote to Effects, loot and item use to Inventory, model build to Building,
behavior sound to Property, skill sets to Skill) and gain the missing
direction. The dismount logic moves to PossessorComponent::OnDismountComplete.

Every inbound message is registered in the GameMessageHandler map; the
switch is gone, and GameMessages.cpp only holds the GameMsg/NetGameMsg base
code. Call sites build the structs (NotifyClientObject, TerminateInteraction,
Teleport, PlatformResync, FireEventClientSide, NotifyObject and
NotifyClientZoneObject get convenience constructors like PlayFXEffect).
Dead senders are dropped: SendSetShootingGalleryParams (no callers, field
order was a guess), SendTeamPickupItem (the struct already existed),
SendRequestActivitySummaryLeaderboardData (the struct covers it).

Verified with RemainingMessagesTests: every old Send* function is frozen
verbatim in Legacy/RemainingMessagesLegacy.h and compared byte for byte
(same bits, destination and broadcast flag) over grids of inputs; every old
Handle* read sequence is frozen as a Read* oracle and compared with the
struct's Deserialize; round trips, truncation and a golden packet.
PlayerLoaded (0x00dc36f0), SetGMLevel (0x00dd6230), MissionDialogueCancelled
(0x00d9cc10) and LocalizedAnnouncementServerToSingleClient (0x00f23c50)
were checked against the client. Behaviour notes: an inbound message that
fails to deserialize is dropped, so ParseChatMessage over MAX_MESSAGE_LENGTH
is dropped instead of truncated, and PLAYER_LOADED / READY_FOR_UPDATES /
MISSION_DIALOGUE_CANCELLED now read their (unused) client fields.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

dGame/dGameMessages/ActivityMessages.h

@@ -2,6 +2,8 @@
 #define ACTIVITYMESSAGES_H
 
 #include "GameMessages.h"
+#include "NiQuaternion.h"
+#include "eMatchUpdate.h"
 
 #include <string>
 
@@ -83,6 +85,112 @@ namespace GameMessages {
 		std::u16string sndName{};
 		int32_t stateToPlaySoundOn{};
 	};
+
+	// Server -> client, to one client.
+	struct MatchResponse : public NetGameMsg {
+		MatchResponse() : NetGameMsg(MessageType::Game::MATCH_RESPONSE) {}
+		void Serialize(RakNet::BitStream& bitStream) const override;
+		bool Deserialize(RakNet::BitStream& bitStream) override;
+
+		int32_t response{};
+	};
+
+	// Server -> client, to one client.
+	struct MatchUpdate : public NetGameMsg {
+		MatchUpdate() : NetGameMsg(MessageType::Game::MATCH_UPDATE) {}
+		void Serialize(RakNet::BitStream& bitStream) const override;
+		bool Deserialize(RakNet::BitStream& bitStream) override;
+
+		// Name-value (LDF) text. Each byte is widened to one UTF-16 unit on the wire.
+		std::string data{};
+		eMatchUpdate type{};
+	};
+
+	// Client -> server. Join (type 0, value = activity ID) or ready/unready (type 1, value = ready) a match.
+	struct MatchRequest : public NetGameMsg {
+		MatchRequest() : NetGameMsg(MessageType::Game::MATCH_REQUEST) {}
+		void Serialize(RakNet::BitStream& bitStream) const override;
+		bool Deserialize(RakNet::BitStream& bitStream) override;
+		void Handle(Entity& entity, const SystemAddress& sysAddr) override;
+
+		LWOOBJID activator{};
+		// Name-value (LDF) text, narrowed to one byte per character as DLU always did.
+		std::string playerChoices{};
+		int32_t type{};
+		int32_t value{};
+	};
+
+	// Client -> server (and server -> client in the client's definition). Answered with the leaderboard.
+	struct RequestActivitySummaryLeaderboardData : public NetGameMsg {
+		RequestActivitySummaryLeaderboardData() : NetGameMsg(MessageType::Game::REQUEST_ACTIVITY_SUMMARY_LEADERBOARD_DATA) {}
+		void Serialize(RakNet::BitStream& bitStream) const override;
+		bool Deserialize(RakNet::BitStream& bitStream) override;
+		void Handle(Entity& entity, const SystemAddress& sysAddr) override;
+
+		int32_t gameID{ 0 }; // optional
+		int32_t queryType{ 1 }; // optional, a Leaderboard::InfoType
+		int32_t resultsEnd{ 10 }; // optional
+		int32_t resultsStart{ 0 }; // optional
+		LWOOBJID targetID{}; // "target" in the client; renamed so it doesn't hide NetGameMsg::target
+		bool weekly{};
+	};
+
+	// Server -> client, to one client (UNASSIGNED broadcasts). The payload is written by Leaderboard::Serialize.
+	// When a client sends it, nothing is read (DLU only logs it).
+	struct SendActivitySummaryLeaderboardData : public NetGameMsg {
+		SendActivitySummaryLeaderboardData() : NetGameMsg(MessageType::Game::SEND_ACTIVITY_SUMMARY_LEADERBOARD_DATA) {}
+		void Serialize(RakNet::BitStream& bitStream) const override;
+		void Handle(Entity& entity, const SystemAddress& sysAddr) override;
+
+		const Leaderboard* leaderboard{};
+	};
+
+	// Server -> client, to one client (UNASSIGNED broadcasts).
+	struct NotifyClientShootingGalleryScore : public NetGameMsg {
+		NotifyClientShootingGalleryScore() : NetGameMsg(MessageType::Game::NOTIFY_CLIENT_SHOOTING_GALLERY_SCORE) {}
+		void Serialize(RakNet::BitStream& bitStream) const override;
+		bool Deserialize(RakNet::BitStream& bitStream) override;
+
+		float addTime{};
+		int32_t score{};
+		LWOOBJID targetID{};
+		NiPoint3 targetPos{};
+	};
+
+	// Client -> server. Nothing is done with it.
+	struct UpdateShootingGalleryRotation : public NetGameMsg {
+		UpdateShootingGalleryRotation() : NetGameMsg(MessageType::Game::UPDATE_SHOOTING_GALLERY_ROTATION) {}
+		void Serialize(RakNet::BitStream& bitStream) const override;
+		bool Deserialize(RakNet::BitStream& bitStream) override;
+
+		float angle{};
+		NiPoint3 facing{};
+		NiPoint3 muzzlePos{};
+	};
+
+	// Client -> server.
+	struct ShootingGalleryFire : public NetGameMsg {
+		ShootingGalleryFire() : NetGameMsg(MessageType::Game::SHOOTING_GALLERY_FIRE) {}
+		void Serialize(RakNet::BitStream& bitStream) const override;
+		bool Deserialize(RakNet::BitStream& bitStream) override;
+		void Handle(Entity& entity, const SystemAddress& sysAddr) override;
+
+		NiPoint3 target{};
+		NiQuaternion rotation = QuatUtils::IDENTITY; // written w, x, y, z
+	};
+
+	// Client -> server.
+	struct ActivityStateChangeRequest : public NetGameMsg {
+		ActivityStateChangeRequest() : NetGameMsg(MessageType::Game::ACTIVITY_STATE_CHANGE_REQUEST) {}
+		void Serialize(RakNet::BitStream& bitStream) const override;
+		bool Deserialize(RakNet::BitStream& bitStream) override;
+		void Handle(Entity& entity, const SystemAddress& sysAddr) override;
+
+		LWOOBJID objectID{};
+		int32_t value1{};
+		int32_t value2{};
+		std::u16string stringValue{};
+	};
 };
 
 #endif // ACTIVITYMESSAGES_H